Subaqueous barchan dunes in turbulent shear flow. Part 1. Dune motion

  title={Subaqueous barchan dunes in turbulent shear flow. Part 1. Dune motion},
  author={Erick de Moraes Franklin and François Charru},
  journal={Journal of Fluid Mechanics},
  pages={199 - 222}
Experiments are reported on the formation and migration of isolated dunes in a turbulent channel flow. These dunes have a very robust crescentic shape with horns pointing downstream, very similar to that of the barchan dunes observed in deserts at a much larger scale. Their main geometrical and dynamical properties are studied in detail, for four types of grains: the conditions for their formation, their morphology, the threshold shear stress for their motion, their velocity, erosion rate… Expand
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